Keira Knightley's corset claim

Keira Knightley has claimed corsets are the reason women were always considered "the weaker sex".

She told Hamptons magazine: It's obvious why women were called the weaker sex, because you can hardly breathe in a corset

The 23-year-old actress - who has donned the restrictive undergarments in period dramas including 'Pride and Prejudice' and 'The Duchess' - says the waist cinchers stopped oxygen getting to the brain, making females seem less intelligent than they were.

She told Hamptons magazine: "It's obvious why women were called the weaker sex, because you can hardly breathe in a corset. It's a fight just to get oxygen to your brain."

Keira, who reportedly has a tiny 23-and-a-half-inch waist, has previously revealed how difficult she found wearing the tight costumes in her various films.

Speaking about her role in 'The Duchess', in which Keira played Georgiana, the Duchess of Devonshire, she said: "I had quite a few different corsets, and it was really weird because they were all obviously made to measure for me, but some of them I could breathe in, and some of them I absolutely couldn't... and it was a complete nightmare!"